One problem in designing chips with multiple resistors is to ensure that all resistors designed to have the same resistivity will match in the final product, so that the circuit works properly. One factor that adds further complexity to the task of matching TFRs across a chip is the desire to hold down costs by limiting the number of steps and the number of masks required to incorporate a process that forms the TFRs. The inclusion of multiple thin film resistors that require different resistance values can further complicate the process. Improvements are needed.